painting trailer-sandblasting qeustion

[jdsgrog]

I'm hoping this is in the right topic.

I'm planning on repainting an old trailer that holds my 14ft runabout. The trailer is not very large, maybe about 15-16 ft in length. Paint is chipping away and it has a lot of surface rust. To remove the paint and rust, I decided I want to take a stab at sandblasting the trailer. I've studied it and seen it done so I want to try it. I figure if it's too hard to do, I could always take a wire brush to the trailer.

Anyway, I have a couple of questions:
1. How much sandblasting medium is generally required?
2. Since I plan to do this outside, I'm planning on using a biodegradable medium. Is there a way to contain the medium for reuse or is it pretty much done with the first use?

 

[marlboro180]

Re: painting trailer-sandblasting qeustion

Anyway, I have a couple of questions:
1. How much sandblasting medium is generally required?
2. Since I plan to do this outside, I'm planning on using a biodegradable medium. Is there a way to contain the medium for reuse or is it pretty much done with the first use?

Well, I dont know if this is the right place either , but here is my experience:

Blasting is way better that wire wheeling. In response to question 1, I used about 2 1/2 bags ( 80 # ea) of open silica sand to do a complete paint/rust removal on my trailer .( Boat is 18 foot, no idea on trailer length) I had tried black beauty, but left the surface a little too rough for my liking. This was done outside using a pressure pot sandblaster.

I regards to your desire to re-use the blasting medium, I would not bother. You are gonna get a lot of chips/ rust scale, tiny rocks and other debris when you reclaim it that will just clog your blaster. Sweep it up and use it for traction sand in the winter.

Just curious- What do you consider biodegradable medium? In my eyes sand should fit the bill just fine.

 

[arks]

Re: painting trailer-sandblasting qeustion

Yeah, sandblasting is definitely the way to go.
I've sandblasted a couple trailers in the past. Last one I did in one of those portable 'garages' from Harbor Freight. I put plywood on the ground so I could sweep.
Recovery of media depends largely on your equipment. I use a simple venturi-type sandblaster and find that second-hand sand works fine. When I get a clog, it's easy to clear by covering the nozzle and 'backwashing' air thru the tube.

 

[Bondo]

Re: painting trailer-sandblasting qeustion

Ayuh,... Never heard of biodegradable sand before,..??

I'd start with atleast 100lbs...
For material recovery, put out a Big blue tarp,+ park the trailer on it...
When you pick up the recovered material, stiff it through a window screen before reusing,...
It'll cut down on the clogs...
I've got a pressure-pot blaster,... Never had alota luck with a siphon unit...

 

[jdsgrog]

Re: painting trailer-sandblasting qeustion

thanks everyone. i was planning on using a soft blasting material like walnut shells. I thought about the tarp idea and using aluminum oxide, but I wasn't sure how much is blown around.

 

[109jb]

Re: painting trailer-sandblasting qeustion

If you have access to a gas powered pressure washer then get one of the units in the link below. The unit has a quick connector that plugs on where the nozzles normally go. I use this quite often and it works great. Instead of air being used to propel the sand the water from the pressure water does the job. Works better than the pressure pot I have and is a lot less messy. If you do use this you will not be re-using the sand though. I have a 5 gallon bucket with a hole cut in it to fit the size of the pickup hose. You might think that using water will make the rust worse, but I just dry whatever I am blasting off with a towel and compressed air. The most I ever get is a haze of surface rust that just wipes off with metal prep.

Also, if using a standard sandblaster, silica sand used in sandblasting is known to cause silicosis which is a respiratory disease that can be fatal. You won't find many commercial sandblast operations using sand containing silica. I wouldn't use it for conventional sandblasting unless I was using a full face powered air purifying respirator (PAPR). That is another benefit of the water sandblaster. The water keeps the sand from releasing the free silica. Basically there is no big cloud of dust like conventional sandblasting.

My 2 cents.

Here is that link to the water sandblaster.



Sandblaster for pressure washer

 

[jdsgrog]

Re: painting trailer-sandblasting qeustion

Sadly, I don't have a pressure washer. It's one of my "future purchase" lists. But since I don't own a garage (I live in a condo and rent a garage), never had a need for one.

That's right about the silicosis. I remember reading about that and was planning to stay away from it. Does anyone know where one can get blasting media for a decent price? I live in the city of Chicago, but online stores are fine as well.

 

[109jb]

Re: painting trailer-sandblasting qeustion

If you are looking for sand type blasting media, Menards has the black silica free stuff. They keep it inside near the bags of concrete. Lowes and Home Depot probably have it too, but I know my local menards has it. Harbor Freight also carries various types of blasting media.

 

[q5ka]

Re: painting trailer-sandblasting qeustion

Harbor Freight is one place to consider for sand blast material if you was thinking walnut. I use it in my blasting cabinet and it is good enough for that. Also, agree with Bond-O, you can reuse as long as you can filter out the bigger chunks. If a piece of rust scale is the same size as the blast media, it is just going to flow through with the blast media. If its bigger, it will clog.

 

[kabcpapc]

Re: painting trailer-sandblasting qeustion

Northern Tool also has a good selection of blasting media.

 

[jdsgrog]

Re: painting trailer-sandblasting qeustion

Yeah, I was looking at harbor freight. I have one somewhat locally (in the burbs). I'll also take a look at menards of the black silica free material. Thanks everyone.

 

[Peter_Crowl]

Re: painting trailer-sandblasting qeustion

If you're in the Chicago burbs why not price out having it done by a sandblasting shop?
I pay about $100 to do a trailer your size...add up the costs and hassle of doing it yourself and you'll probably find it's better to have it done

Peter
in Denver

 

[jdsgrog]

Re: painting trailer-sandblasting qeustion

I've looked around, but here in Chicago, things are more expensive than I'd like it to be. I"m getting estimates from $250 to $400. If you know anyone that can do it for $100-$150, let me know.

BTW, I actually live in the city. But the burbs are easily accessible.